| Summary: |
This draft study of two specific nanotechnology applications, titanium dioxide in water treatment and topical sunscreen, is intended to be a foundation for the development of “scientific and technical information needed for future assessment efforts.” The EPA encourages readers to comment on specific “knowledge gaps” which exist in this draft, and to offer suggestions as to how these gaps may be better addressed in the future. The comprehensive environmental assessment (CEA) approach taken in this document combines a life-cycle framework with a risk assessment paradigm, examining the direct and indirect effects of titanium dioxide throughout a product’s life cycle, including disposal. In order, the study examines the stages of the life cycle in question, fate and transport processes, exposure-dose characterization, and ecological and health effects. This document is not intended to provide an actual CEA of titanium dioxide, but only to identify which information is known and needs to be known to conduct an comprehensive assessment of similar nanomaterials in the future. |